Sun Wukong (Stephen Chow) escorts Tang Sanzang (Law Kar-ying) to the West to obtain Buddhist scriptures. On the way, he conspires with Bull Demon King to kill Tang Sanzang and steals the Moonlight Box. This action makes Guanyin want to eradicate him. At Tang Sanzang's request, Sun Wukong is sentenced to reincarnate as a human in 500 years to atone for his sins. 500 years later, Sun Wukong becomes the bandit leader Zhizunbao. When he met the monster sisters, the spider spirit Chun Sanshi Niang (Anita Mui) and the bone spirit Bai Jingjing (Karen Mok), who planned to eat Tang Monk's flesh, Zhizunbao fell in love with Bai Jingjing at first sight because Sun Wukong had a relationship with Bai Jingjing five hundred years ago. However, because Patriarch Bodhi told him the identities of the two monsters, Zhizunbao still led the robbers to deal with the two monsters. In the process, Bai Jingjing injured Chun Sanshi Niang in order to save Zhizunbao, and she was also poisoned and injured. In order to save Bai Jingjing, Zhizunbao went to find Chun Sanshi Niang, but was misunderstood by Bai Jingjing and committed suicide in despair. Zhizunbao began to use the Moonlight Box in the hope of turning back time.